Cheap talk box?
I made a homemade talkbox a few years back that sounded pretty spot on. Total cost was about $30.
What you’ll need:
Cheap plug in laptop speakers ($10)
Duct tape ($5)
Two toilet plungers ($15)
5′ of garden hose (Free – Just go chop a length of it from your front yard.)
Take the laptop speakers and cut off the one that doesn’t have the volume knob on it. Now take the remaining speaker apart: remove the plastic case so that the speaker and innards are exposed.
Take the wooden handles out of the plungers and cut out the bottom of the holes that the wood goes into. Place the laptop speaker inside one of the plungers, with the magnet facing out and the speaker cone facing the small hole. Duct tape it in place. Place the second plunger behind the speaker to essentially enclose the speaker inside the two plungers.
Take your length of garden hose and place one end into the hole that the wooden handle was in, with the hose pointing at the speaker cone. Duct tape it in place.
Now all you do is plug the speakers into the headphone out, line out, external out etc., of your amp.
Here’s an example of what that exact build will sound like (8:48 to hear it)
[ame=http://www.youtube.com/watch?v=wLxpHMo4fMs&t=8m48s]Build a Not so Ghetto Talk box out of a Toilet Plunger – YouTube[/ame]